package com.study.notepad.util;

import java.util.Random;

public class RandomValueUtil {

    public static String randomString(Integer length) {
        String val = "";
        Random random = new Random();
        for (int i = 0; i < length; i++) {
            // 判断生成数字还是字母(字母有大小写区别)
            String charOrNum = random.nextInt(2) % 2 == 0 ? "char" : "num";
            // 输出字母还是数字
            if ("char".equalsIgnoreCase(charOrNum)) {
                // 输出是大写字母还是小写字母
                int temp = random.nextInt(2) % 2 == 0 ? 65 : 97;
                val += (char) (random.nextInt(26) + temp);
            } else if ("num".equalsIgnoreCase(charOrNum)) {
                val += String.valueOf(random.nextInt(10));
            }
        }
        return val;
    }

    public static String randomNumber(Integer length) {
        Random random = new Random();
        String result = "";
        for (int i = 0; i < length; i++) {
            result += random.nextInt(10);
        }
        return result;
    }

    public static void main(String[] args) {
        System.out.println(RandomValueUtil.randomString(8));
    }
}
